Thankfully, air conditioners keep us cool and comfortable during these sizzling summer days. More than 60% of US households now have central air conditioning, up from 23% in the late 1970s. But the luxury of A/C comes at an obvious cost: higher electricity consumption. Exactly how much higher? We found that the average home’s electricity usage on a 103°-high summer day is up to 40% higher than during a typical summer day.

How do we know? We cracked open our data warehouse to examine anonymized energy usage data across 18,000 homes from 3 different cities in the western part of US, which has faced blistering temperatures this summer. In particular, we explored a few key questions about energy consumption on hot days: